Password protected Word/phishing emails

[Alex]

Hi,

I'm using amavisd-new-2.11.0 on fedora23 with spamassassin and clamav.
I'm starting to receive password encrypted Word documents similar to
this:

http://pastebin.com/HpvEcT9K

How can I configure amavisd to either change the subject or otherwise
block emails with encrypted Word documents? Is it possible for virus
scanners to detect malicious emails that have been password protected?

Thanks,
Alex